Every electronic device has a demand for a specific voltage in the modern era of electronic technology. Therefore, a voltage regulator is needed for the electronic device to meet specification of power. The voltage regulators commonly used in the market are switching regulators which do not generate heat easily and output voltages thereof are able to be adjusted by switch elements inside thereof to steadily output to external load elements. However, overshooting always occurs when the output voltage of the switching regulator increases, and causes a malfunction of electronic elements. The switching regulator can be added with other electronic elements to prevent overshooting, but this would increase manufacturing costs. How to solve the aforementioned problem has become an issue in the industry.